Why?

From a young age I can remember hearing and discussing the question that will always be one of the most important, most poignant questions of our age.  If there is a God, how could he let the Holocaust happen?  Six millions Jews killed.  For what?  To many who went through that time they would come out questioning whether God existed at all.  There were some who said it happened so that the modern State of Israel could be born.  Many would come to the conclusion that we will never know why it happened because there is no explanation why man could resort to such evil.  And many survivors would ask why it was they would live while others will die.  I will share my thoughts on the subject later, but right now I am hoping to get input from all of you reading this post.